Syntheses and supramolecular structures of two 5-nitrosalicylate titanocene complexes

摘要

Two 4-coordinated titanocene complexes,[(eta~5-C_5H_5)_2Ti(O,O')(5-NO_2-OCC_6H_3)] (I) and [(eta~5-C_5H_5)_2Ti(2-OH-5-NO_2-O_2CC_6H_3)_2] (II),have been synthesized by reaction of Cp_2TiCl_2 and 5-nitrosalicylic acid in aqueous media.Single-crystal X-ray analyses of I and II display the mononu-clear forms of Ti~(IV),and geometries at titanium atoms are distorted tetrahedrons,while the coordination environment at Ti~(IV) in complex I is different from that in complex II.Crystallographic characterization revealed that each of the complexes exhibits a three-dimensional framework constructed through weak interactions,which are H-bonding,pi-pi stacking and C-H...pi interactions,but they differ greatly when forming the three-dimensional network structure in both complexes.The results show that the dramatic change of conditions has great effect on the molecular structure of 5-nitrosalicylate titanocene,thereby significantly influencing the weak interactions and the specific framework structure.